1. Field of the Invention
This invention relates to a reproduction apparatus and a reproduction method by which digital information recorded on a disk-type recording medium can be reproduced.
2. Description of the Related Art
In recent years, disk media onto and from which audio data can be recorded and reproduced such as, for example, a mini disk (MD) and recording and reproduction apparatus on which such disk media can be used have been popularized widely.
Also an audio system which includes a combination of, for example, an MD recorder/player which is a recording and reproduction apparatus for an MD and a CD player or the like has been popularized widely.
In such a system as an MD recorder/player and a CD player or the like as described above, audio data are managed in a unit called a “program”. Here, a program in the present specification signifies a set of data which are managed and recorded in a unit on a disk, and for example, with regard to audio data, it corresponds to one tune (generally called a “track”) or the like. Therefore, in the following description, a program may suitably be referred to as a track.
Such an audio system as described above is usually constructed such that it can effect dubbing recording, that is, recording of audio data reproduced by the CD player onto an MD by the MD recorder/player.
Also a system which can effect high speed dubbing to reduce the recording time is available.
Upon high speed dubbing, a disk rotational driving control system and a reproduction signal processing system of the CD player are controlled so that a CD may be reproduced at a predetermined multiple speed higher than a normal reproduction speed. Also on the MD recorder/player side, a recording signal processing system is controlled so as to operate at a multiple speed corresponding to the reproduction multiple speed for a CD, and receives audio data reproduced by the CD player and records the audio data onto an MD.
For example, in an apparatus wherein a CD player as a reproduction apparatus and an MD recorder/player as a recording apparatus are integrated with each other, it is easy to control the CD player and the MD recorder/player so that they may simultaneously operate at a predetermined multiple speed so as to perform such high speed dubbing as described above. Also in another system wherein a reproduction apparatus and a recording apparatus are formed as separate units from each other, if the system is constructed such that, for example, a controlling cable or the like is used to connect the reproduction apparatus and the recording apparatus to each other so as to communicate with each other, then high speed dubbing can be realized readily by controlling operations of the reproduction apparatus and the recording apparatus in synchronism with each other.
In an accessing operation of the reproduction apparatus side upon such high speed dubbing, a start address of an object track is accessed first while a disk is driven to rotate at a predetermined multiple speed.
However, it is known that, while a disk is being rotated at a high speed, it is difficult to appropriately effect a leading-in operation of tracking servoing if accessing such as, for example, feeding of an optical head along a radial direction of a disk is involved.
It is considered that this arises from the fact that, since, for example, when a disk is rotated at a high speed, the disk whirls in a shorter period with regard to a radial direction of the disk which is caused by eccentricity of the disk, also tracks formed along a circumferential direction of the disk whirl in a shorter period and tracking servoing is less liable to follow up a track.
When it is tried to actually execute high speed dubbing in such a situation as described above, if tracking servo control is not executed appropriately in such a manner as described above, then the possibility increases that such a disadvantage that, for example, on the recording apparatus side, since a PLL (Phase Locked Loop) circuit for detecting a channel clock signal suitable for recording data inputted thereto cannot establish a locked condition, recording signal processing cannot be executed appropriately in synchronism with the recording data supplied from the reproduction apparatus side may increase.
One of possible countermeasures for solving the problem described above is, for example, to drive a CD to rotate at a high multiple speed as a CAV (Constant Angular Velocity) whereas a CD is usually driven to rotate at a CLV (Constant Linear Velocity) as well known in the art. Further, a buffer memory such as a DRAM (Dynamic Random Access Memory) is provided and used such that data read out from a CD are stored once into the buffer memory and then signaled to the MD recorder/player side at a transfer rate lower than the rate upon writing.
Where the system is constructed in this manner, for example, even if tracking leading-in control for a CD is retried as a result of an error therein, data stored already in the buffer memory can be supplied as recording data to the MD recorder/player side. Then, if the CD player succeeds in the retrying of the tracking leading-in control for the CD and re-starts reproducing the CD before the data stored in the buffer memory are all signaled, then the continuity of recording data is maintained.
However, where the system has the construction described above, it is necessary to additionally install a memory element as the buffer memory and adopt a new construction for communication with a main system controller (microcomputer). Consequently, increase of the cost and the circuit scale cannot be avoided.
Further, in this instance, it is necessary for practical use to raise the error correction capacity for reproduction data (for example, error correction processing for C1 and C2 parities is set heavier than double or quadruple to raise the error correction capacity). This increases a processing burden.